This paper establishes a dynamics model for deploying solar panels with clearances by using a practical method and provides a useful way to identify the effects of clearances on spacecraft systems. Considering the clearance of joints, a contact dynamic model is established using the nonlinear spring-damp model and the friction effect is considered by using the Coulomb friction model. Based on t...

The attitude dynamics of a satellite with a large magnetic residual dipole is analysed and the effect of perturbations of the orbital parameters on stability is discussed. The analysis is the basis for the design of an attitude control strategy that minimizes the required control torque while satisfying an absolute pointing error constraint whenever direct compensation of magnetic torque is not...

With the growing popularity of small satellites, interaction with air in low and especially very Earth orbits becomes a significant resource for passive angular stabilisation. However, possibility spin motion remains considerable challenge missions involving aerodynamically stabilised satellites. The goal this paper was to investigate attitude arbitrarily spinning satellites LEO VLEO under acti...

This article presents a unified synchronization framework with application to precision formation flying spacecraft. Central to the proposed innovation, in applying synchronization to both translational and rotational dynamics in the Lagrangian form, is the use of the distributed stability and performance analysis tool, called contraction analysis that yields exact nonlinear stability proofs. T...

This paper considers the problem of attitude sensor fault diagnosis in a quadrotor helicopter. The proposed approach is composed of two stages. The first one is the modelling of the system attitude dynamics taking into account the induced communication constraints. Then a robust fault detection and evaluation scheme is proposed using a post-filter designed under a particular design objective. T...

This paper explores whether an individual’s news source can explain their attitudes on immigration. We focus on the Spanish-speaking population in the U.S., since they have the option of accessing their news in English, Spanish or in both languages. Our audience influence hypothesis predicts that Spanish-language news will cover immigration in a more positive and informative manner than will En...

To better understand the historical pattern of sport participation in Japan, two active elderly groups-Masters athletes and senior university students-were compared. Research findings suggest that Masters athletes perceive sport as serious and competitive, and their previous sport participation leads directly to their sport participation in later life. On the other hand, senior university stude...

Previous research has characterized toll free hotline users, but has not evaluated their satisfaction with this consumer service. Using a telephone survey of callers to the state-established Wisconsin consumer protection "Hotline," we study satisfaction with the Hotline and related services. Subgroups of the Wisconsin population that use the Hotline are identified. A related assessment examines...

This addition to the spacecraft dynamics and control literature joins a fairly short list of texts that treat control of both orbit and attitude dynamics, including Bryson’s Control of Spacecraft and Aircraft (1994), Kaplan’s Modern Spacecraft Dynamics and Control (1976), and Wiesel’s Space ight Dynamics (1996). As the subtitle indicates, a novel aspect of this text is its emphasis on the “pra...

This paper presents an algorithm for velocity-aided attitude estimation for helicopter aircraft using a microelectromechanical system inertial-measurement unit. In general, high- performance gyroscopes are used for estimating the attitude of a helicopter, but this type of sensor is very expensive. When designing a cost-effective attitude system, attitude can be estimated by fusing a low cost ac...